Crossrail update on the Elizabeth line’s opening plans

The Elizabeth line is entering the final phases of testing and software upgrades ahead of opening the line to the public, TfL’s Commissioner, Andy Byford has confirmed. Ahead of this week’s Elizabeth line committee meeting, and at last week’s Transport Committee meeting, more details were given about the final pieces of work needed to open the line.

Now that the mass testing is over the line is in timetabled running, closely mirroring the Elizabeth line service timetable. This will be the final stage before the railway will open and its duration will be determined by the ability to demonstrate improved reliability across the railway.

Ahead of the opening though, there are further upgrades planned to the trains and signalling software over the Easter period, including the commissioning of the ELR200 software and Alstom 5.6 and 5.7 software upgrade. These upgrades are expected to provide increased operational reliability of the trains, routeway and signalling systems.

At last week’s GLA Transport Committee meeting, Andy Byford confirmed that the trains aren’t quite as reliable as he wants them yet, although he added that it’s not so much the trains themselves, but the way they connect with the signalling systems that are causing the issues.

He cited specific system interfaces at specific locations as causing problems. One example given is at Stratford where something is causing the trains to come to an emergency stop. That’s what the trains are supposed to do when they detect something is wrong, and it just needs a reset for the trains to carry on, but that’s a problem and it needs fixing.

With a service at intensive as the Elizabeth line is planned to offer, a momentary delay caused by one stopped train can also cascade down the line causing longer delays later. So apart from being a bug that shouldn’t be there, it’s also one that could, in theory, affect the line when it’s open.

Any radio system can be interfered with by other electronics, and often debugging them can be remarkably difficult when they seem to be randomly occurring. Most radio and electronics engineers have war tales of trying to find some weird oddity that’s messing their radios, and the sigh of both deep relief at finding it, and deep frustration at how tiny it often was when found.

Often it’s a weird combination of low-level emissions that just hit the bad spot if they all happen at once or a badly shielded item that’s only occasionally used. There are the famous stories of microwave ovens interfering with a radio telescope to one of the UK’s earliest business computers throwing a random wobble, which was isolated to electrics in the lift shaft next to the computer room, and it only went wrong when the lift went to the top floor.

The issue for the Elizabeth line at Stratford appears to be the boundary between signalling systems, and last week the technicians said that they think they’ve identified the problem after scouring the area with sensors and testing kit to look for electronic noise in the area.

Work is underway to fix the remaining bugs discovered with the signalling system and work has been already completed to remove the last restriction on the railway’s infrastructure. Additional software upgrades for the tunnel vent system will coincide with the commissioning of the train software upgrades around Easter.

The meeting papers warn that the aim of bringing the Elizabeth line into passenger service within the first half of this year is “under pressure”, but is still likely to happen. Andy Byford reiterated that the core tunnels of the Elizabeth line will open by the end of this June.

He also confirmed that he still won’t open the line until he’s confident it’s reliable and has had several weeks of stable running of the line in timetabled service before letting passengers on board.

Elsewhere, Bond Street is now about three months behind the rest of the line opening – so estimated to open in the autumn. There had been some talk of partially opening Bond Street by focusing work on one of the two entrances. However, it turned out that separating the fire safety systems to allow that was more expensive and take longer than it would to just focus on opening the station.

Also, the current funding situation is that the project is within the previously announced requirement of £1.1 billion, but as only £825 million was offered by the DfT, there’s a gap between the two. The projected cost of completing the project is currently £174 million above the £825 million that’s available, so negotiations to find the rest of the money are ongoing.

As for the process after the line opens, there are two upgrades planned.

One due to take place later this year is to link Shenfield to Paddington and Abbey Wood to Reading, and to increase the number of trains in the core tunnels to 22 trains per hour. That was scheduled for the December timetable change with Network Rail, but they are now confident that it can be deployed sooner than that. So sometime in the autumn — maybe even syncing with the opening of Bond Street station.

The final upgrade to fill in the gaps and raise the frequency to 24 trains per hour does need to be synchronised with Network Rail in May 2023.